There are many background documents relating to fields of mirrors that can be oriented, but specifically relating to the longitudinal horizontal planar case, international application WO 99/42765 is mentioned, in which the receiver is a longitudinal tube similar to that used in parabolic trough collectors like that described in U.S. Pat. No. 4,243,019 and several others. Other background documents worth mentioning include the following: WO 2009/029277 A2 disclosing a conventional Fresnel reflection configuration with multi-tube receiver, and a number of configuration variants, though without numerical assembly requirements and with very generic claims; using planar mirrors in FIGS. 3 and 4 and concave mirrors, without further specification, in FIG. 12, also discussing the configuration of hydraulic circuits in the multi-tube receiver, without taking into account the natural aperture of sunlight; WO 2009/023063 A2 discloses a receiver inclined with respect to the ground with an asymmetric structure to favor collecting radiation; WO 2006/000834 A1 proposes mirrors with multiple planar facets, and it further relates to mechanisms for suitably focusing the planar mirrors on the receiver; WO 02/12799 A2 discloses a bi-parabolic concentrator around the receiver tube which mentions, without geometric specifications, “flat rotating mirrors” in the field of mirrors in claims 9 and 10; WO 02/02995 A2 relates to a basic Fresnel reflection system with a novel modality for supporting the tube; EP 2 161 516 A1 relates to a classic Fresnel reflection system in which propagation of the beam with the concentration characteristic of concave mirrors is envisaged, though it does not claim any requirement on the shape of such mirrors; BE 1 013 565 A3 discloses an absolutely basic Fresnel reflection, cited as a background in some of the aforementioned patents and using mirrors with multiple planar facets; BE 1 013 566 A3 also discloses Fresnel reflection, in this case with concave mirrors to concentrate the radiation on the tube receiver, though without specifying equations for defining the profiles of the mirrors or submitting illustrative drawings on the problem with concentration of solar radiation due to its natural aperture.